Method and apparatus for delivering sheets

ABSTRACT

A first pair of endless chain conveyors have transverse gripper bars thereon with gripper devices that are arranged to engage the front edge of a sheet while the sheet is being printed in a printing unit. The first pair of endless chains convey the sheet to an intermediate transfer cylinder where the front edge of the sheet is transferred from the transverse gripper bars to the transfer cylinder. The tail edge of the sheet is engaged by tail edge grippers on the intermediate transfer cylinder. The front edge of the sheet is transferred from the intermediate transfer cylinder to gripper devices associated with a plurality of endless chain conveyors to which gripper devices are connected. The gripper devices convey the sheet from the transfer cylinder to the pile. A slowdown device is arranged to reduce the forward movement of the sheet as the front edge of the sheet approaches the front edge of the pile and the tail edge grippers are arranged to release the tail edge of the sheet after the front edge of the sheet has been released by the grippers on the plurality of endless chain conveyors. The plurality of endless chain conveyors are movable longitudinally relative to the transfer cylinder to thus deliver different sized sheets to a pile. The transfer cylinder is also adjustable so that sheets of different length may be transferred thereon.

United States Patent [191 Carricato METHOD AND APPARATUS FOR DELIVERINGSHEETS Primary Examiner-James B. Marbert Assistant Examiner-Bruce H.Stoner, Jr. Attorney, Agent, or Firm-Stanley J. Price, Jr.

i am 3,841,625

[4 51 Oct. 15, 1974 [57] ABSTRACT A first pair of endless chainconveyors have transverse gripper bars thereon with gripper devices thatare arranged to engage the front edge of a sheet while the sheet isbeing printed in a printing unit. The first pair of endless chainsconvey the sheet to an intermediate transfer cylinder where the frontedge of the sheet is transferred from the transverse gripper bars to thetransfer cylinder. The tail edge of the sheet is engaged by tail edgegrippers on the intermediate transfer cylinder. The front edge of thesheet is transferred from the intermediate transfer cylinder to gripperdevices associated with a plurality of endless chain conveyors to whichgripper devices are connected. The gripper devices convey the sheet fromthe transfer cylinder to the pile. A slowdown device is arranged toreduce the forward movement of the sheet as the front edge of the sheetapproaches the front edge of the pile and the tail edge grippers arearranged to release the tail edge of the sheet after the front edge ofthe sheet has been released by the grippers on the plurality of endlesschain conveyors. The plurality of endless chain conveyors are movablelongitudinally relative to the transfer cylinder to thus deliverdifferent sized sheets to a pile. The transfer cylinder is alsoadjustable so that sheets of different length may be transferredthereon.

7 Claims, 19 Drawing Figures PATENTEU I 5W4 3. 841.625

SHEET 2 OF 8 N H 2 a 2 lvm 0o 3 v a mm mm 3 1 j METHOD AND APPARATUS FORDELIVERING SHEETS BACKGROUND or THE INVENTION 1. Field of the InventionThis invention relates to a method and apparatus for delivering sheetsand more particularly to a method and apparatus for delivering sheets inwhich the sheet is transferred to an intermediate transfer cylinderbetween two separate conveyor devices.

2. Description of the Prior Art U.S. Pat. Nos. 2,093,228 and 3,378,256illustrate apparatus for engaging the rear edge of the sheet as thesheet is conveyed by the delivery mechanism to the pile. In U.S. Pat.No, 2,093,228 the sheet is supported on an endless delivery carrier withsheet supporting surfacesthereon. The sheet is engaged by tail gripperswhich remove the sheets from the endless delivery carriers and depositthe'sheets on one of two piles. U.S. Pat. No. 3,378,256 discloses sheetdelivery slowdown apparatus in which the sheets are engaged andtransported to the pile by grippers on transverse gripper bars securedto endless delivery chains. As the sheet approaches the pile, the rearend of the sheet is engaged by suction devices that slow down the sheetafter the front edge is released by the grippers on the gripper bars.The suction devices travel linearly in the same di rection as the sheetat a reduced velocity to slow down the sheet and thereafter the suctiondevices release the sheet before the sheet is deposited on the pile.

Other arrangements for preventing tail edge flutter of the sheet as itis deposited on the pile include rotary fixed vacuum discs that engagethe tail edge of the sheet and reduce the forward velocity of the sheet.

Where the sheet deliverymechanism is associated with a perfecting pressin which both sides of the sheet are printed in one pass through thepress, it is essential to prevent disturbances of the sheet as it isdeposited on the pile; otherwise markings and other types ofimperfections will appear in the printed surface on the underside of thesheet as it is deposited on the pile. Suction devices, such as suctionwheels and the like, are not suitable slowdown mechanisms for sheetsprinted on both sides because the sheets will mark where they areengaged by the suction devices. There is a need for delivery apparatusthat engages both the front edge and rear edge of the sheet and reducesthe forward velocity of the sheet before the sheet is deposited on thepile without imparting disturbances as tail edge flutter in the sheetduring further slowdown.

The known sheet delivery devices require substantial dismantling andadjustment to deliver different sized sheets to the pile. There is alsoa need for a sheet delivery device that can be rapidly adjusted fordelivering different sized sheets.

SUMMARY OF THE INVENTION This invention relates to a sheet deliverymechanism for delivering sheets from a printing unit to a pile andincludes a first endless conveyor with sheet engaging means thereon, anintermediate transfer cylinder rotatably mounted between the firstendless conveyor and a pile of sheets. The intermediate transfercylinder has sheet engaging means thereon. A second endless conveyorhaving sheet engaging means thereon is positioned adjacent to theintermediate transfer cylinder and in overlying relation with the pile.The first endless conveyorsheetengaging means is arranged to engage thefront edge'of the sheet and convey the sheet from aprinting unit to theintermediate transfer cylinder. Theintermediate transfer cylinder isarranged to transfer the front edge of the sheet from the first endlessconveyor to the second endless conveyor sheet engaging means and thesecond endless conveyor sheet engaging means is arranged to engage thefront edge of the sheet and convey the sheet into overlying relationwith the pile.

The intermediate transfer cylinder has both sheet front edge engagingdevices and sheet tail edge engaging devices. The tail edge engagingdevices are arranged to release the tail edge of the sheet after thefront edge of the sheet has been released by the sheet engaging means onthe second endless conveyor. A slowdown device is positioned adjacentthe front edge of the pile and is arranged to reduce the forward speedof the second conveyor sheet engaging means. An adjustment means is alsoprovided to move the second endless conveyor longitudinally to deliverdifferent sized sheets to the pile.

The method for delivering a sheet from a printing unit to a pileincludes engaging the front edge of the sheet by a first endlessconveyor while the sheet is in a printing unit. The sheet is conveyed bythe first endless conveyor to an intermediate transfer cylinder wherethe front edge of the sheet is transferred to sheet engaging devices onthe intermediate transfer cylinder while the transfer cylinder isrotating at a preselected speed. The front edge of the sheet isthereafter transferred from the intermediate transfer cylinder to asheet engaging means on a second endless conveyor and the sheet isthereafter conveyed by the second endless conveyor to a pile positionedtherebellow and the sheet is released by the sheet engaging means on thesecond endless conveyor and deposited on the pile.

Accordingly, the principal object of this invention is to provide amethod and apparatus for delivering a sheet in which the sheet isdelivered at a high speed from a printing unit to a pile.

Another object of this invention is to provide a method and apparatusfor delivering a sheet in which both the front and tail edges of thesheet are engaged by gripper devices immediately prior to the sheetbeing deposited on a pile.

These and other objects and advantages of this invention will be morecompletely disclosedand described in the following specification, theaccompanying drawings and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of thedelivery apparatus and the relative position of the delivery apparatusto the impression and blanket cylinders of the last printing unit.

FIG. 2 is a view in section of the transfer cylinder that engages thefront edge and trailing edge of the sheet and transfers the front edgeof the sheet to grippers on a delivery conveyor.

FIG. 3 is a view in section taken along the line Ill-11! of FIG. 2,illustrating the manner in which the segments of the transfer cylindercan be rotated relative to each other to adjust the peripheral distancebetween the sheet front edge gripper and the sheet tail edge gripper.

FIG. 4 is a view in section taken along the line lV-IV of FIG. 2,illustrating the relative position of the front edge gripper and tailedge gripper and in phantom lines an adjusted position of the tail edgegripper to reduce the peripheral distance between the respectivegrippers around the transfer cylinder.

FIG. 5 is a view in section taken along the line V-V of FIG. 2,illustrating the apparatus to rotate the shaft having the tail edgegrippers mounted thereon.

FIG. 6 is a view in section taken along the line VI--VI of FIG. 2,illustrating the endless cam track for the cam follower connectedthrough a lever to a shaft that is arranged to open and close the frontedge grippers.

FIG. 7 is a view in section, taken along the line -Vll- VII of FIG. 5,illustrating another portion of the apparatus for adjusting theperipheral distance between the front edge and tail edge grippers.

FIG. 8 is a view in section taken along the line VIII- VIII of FIG. 5.

FIG. 9 is a schematic view, illustrating the path of the tail edgegrippers during a single revolution of the transfer cylinder.

FIG. 9a is an exploded view of the elements of the tail edge gripper.

FIG. 9b is an enlarged view in elevation of tail edge cam illustratingin phantom the position of the cam follower where the gripper closes onthe sheet and opens to release the sheet.

FIG. 10 is a top plan view of the frame having the chains and gripperguides or track's for delivering the sheet from the transfer cylinder tothe pile.

FIG. 11 is a view in section taken along the line XI-XI of FIG. 10,illustrating the manner in which the frame is adjustable longitudinallyfor different sized sheets.

FIG. 12 is a fragmentary view in side elevation, illustrating one of thegripper guide tracks and the relative position of the frame to thetransfer cylinder.

FIG. 13 is a fragmentary view in section of a gripper positioned in thegripper guide.

FIG. 14 is a fragmentary top plan view, illustrating the manner in whichthe grippers are connected to the chain.

FIG. I5 is a fragmentary view in section taken along the line XV-XV ofFIG. 13, illustrating in detail the actuator for opening the individualgrippers.

FIG. 16 is a schematic illustration of a gripper as the gripper entersthe arcuate portion of the gripper guides before the gripper begins toslow down.

FIG. 17 is a view similar to FIG. 16, illustrating the gripper in theslowed down position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS and a blanket cylinder 14. Anendless chain 16 has a plurality of gripper bars 18 connected theretoand is reeved about a drive sprocket 20 and an idler sprocket 22. Thedrive sprocket 20 is positioned adjacent to the impression cylinder 12and the grippers on gripper bars 18 are arranged to engage the frontedge of the sheet as the sheet is positioned on the impression cylinderand being printed on the outer surface by blanket cylinder 14.

The gripper bars 18 have-a velocity substantially the same as theperipheral velocity of the impression cylinder 12 as the grippers ongripper bar 18 engage the front edge of the sheet and convey the sheetalong the path indicated by the chain 16 and up to the sprocket 22. Thesprocket 22 is mounted on a shaft that is, in turn, supported in adelivery frame 24 that has a transfer cylinder 26 rotatably mountedadjacent thereto. A plurality of delivery chains 34 are mounted abovethe transfer cylinder 26 and have chain sprockets 30 and 32 with theendless chains 34 reeve therearound. Adjacent to the chains 34 are aplurality of gripper tracks 28 with the grippers 36 mounted therein.Grippers 36 are connected to the delivery chains 34 by a push rod aslater explained.

The grippers 36 in the gripper tracks 28 are arranged to engage thefront edge of the sheet while the sheet is on the transfer cylinder 26and convey the sheet forwardly and deposit the sheet on the pile 38. Aslitter mechanism 40 is positioned adjacent the transfer cylinder 26 andis arranged to slit the sheets longitudinally before the sheets aredeposited on the pile 38. As illustrated in FIG. 1, the chains 34 andgripper tracks 28 are movable longitudinally relative to the transfercylinder 26 to accommodate sheets of different length.

The sheet transported by the grippers on gripper bar 18 on the firstchain 16 is arranged to be transferred to front edge grippers 42 oftransfer cylinder 26, as schematically illustrated in FIG. I andillustrated in greater detail in FIGS. 3. 4, and 12. Further rotation oftransfer cylinder 26 transfers the front edge of the sheet from thefront edge grippers 42 on transfer cylinder 26 to the front edgegrippers 36 in gripper tracks 28 associated with the second endlesschains 34. The front edge of the sheet is then conveyed forwardly towardthe pile 38 by the grippers 36 in gripper track 28 and the front edgegrippers 36 in gripper track 28 release the sheet as it is deposited onthe pile. As the tail edge of the sheet approaches the point of tangencybetween the transfer cylinder 26 and the first chains 16, the tail edgeof the sheet is engaged by the tail edge grippers 44. The tail edgegrippers 44, as illustrated in FIG. 9, move outwardly beyond theperiphery of the transfer cylinder 26 while engaged to the tail edge ofthe sheet to slow down the sheet and release the sheet as it isdeposited on the pile.

With this arrangement the sheet is first engaged by the transversegripper bar 18 while the sheet is on the impression cylinder of the lastprinting unit. The sheet is conveyed by the transverse gripper bars 18to the transfer cylinder 26. The front edge of the sheet is transferredfrom the gripper bars 18 to the lead edge grippers 42 in transfercylinder 26 and the lead edge grippers 42 in transfer cylinder 26thereafter transfer the front edge of the sheet to the front edgegrippers 36 mounted in the gripper track 28, and the sheet is thereafterconveyed to the pile 38.

The tail edge of the sheet is engaged by the tail edge grippers 44 ontransfer cylinder 26 and the tail edge of the sheet remains engaged bythe tail edge grippers 44 until the sheet is in substantially overlyingrelation with the pile 38. The grippers 36 first release the sheet todeposit it on the pile and thereafter the tail edge of the sheet isreleased by the tail edge grippers 44 to permit the sheet to bedeposited on the pile without disturbances or flutter. r

The transfer cylinder generally designated by the numeral 26 isillustrated in detail in FIGS. 2 9 and includes a cylinder shaft 48rotatably journaled in side frames 50 and 52. The side of the deliverymechanism 10, including the side frame 50, will also be referred to asthe operators side of the press and the delivery mechanism and theopposite side having the side frame 52 will also be referred to as thedrive side of the press.

Nonrotatably mounted on the shaft 48 are a plurality of spacedcylindrical segments 54 illustrated in FIGS. 3, 4 and 5. The spacedcylindrical segments 54 have cylindrical sheet supporting surfaces 55and the segments 54 will also be referred to as segments or discsassociated with the front edge grippers. Positioned between thecylindrical segments 54 are other cylindrical segments 56 associatedwith the tail edge grippers and will also be referred to as segments ordiscs associated with the tail edge grippers. The discs 56 also havecylindrical sheet supporting surfaces 57 and are adjustably mounted onthe shaft '48. The discs 56 are arranged to rotate about the shaft 48 toincrease or decrease the peripheral distance around the cylinder betweenthe front edge grippers 42 and tail edge grippers 44.

The end discs 56' adjacent to the frames 50 and 52 are illustrated inFIGS. 3 and 5. The end discs 56' have bores 58 therethrough forreceiving the tail edge gripper support shaft 60 and bores 62 to receivethe tail edge gripper actuator shaft 64. The intermediate discs 56, asillustrated in FIG. 4, are connected to the end discs 56' by the angle66 extending longitudinally in the cylinder 26 and secured to pads 68 oneach of the discs 56 and 56'. With this arrangement rotation of the enddiscs 56' about the shaft 48 rotate all of the discs 56 and 56 the sameamount, so that all of the tail edge grippers 44 remain aligned linearlyin various positions of adjustment of the tail edge grippers 44 to thefront edge grippers 42.

The discs 56 and 56 are rotated about the shaft by an adjustmentmechanism illustrated in FIGS. 3, 5, 7 and 8. The end discs 56' includea gear segment 70 that meshes with a pair of gears 72 mounted on shaft74. The shaft 74 is, in turn, journaled in aperture 76 in fixed shaftsupport 75 located adjacent the end discs 56' and nonrotatably securedto the shaft 48 by means of pin 77, as illustrated in dotted line inFIG. 5. With this arrangement the rotation of gear 72, because of itsmeshing relation with the gear segment 70, rotates the enddiscs 56'about the shaft 48 to change the peripheral distance between the tailedge grippers 44 and the front edge grippers 42. The manner in which thetail edge grippers 44 are rotated about the shaft 48 to reduce thedistance between the tail edge grippers 44 and the front edge grippers42 is illustrated in phantom lines in FIG. 4.

The shaft 74 has an adjusting gear 78 (FIGS. 7 and 8) secured to an endportion thereof adjacent the drive side of the press. The gear 78 mesheswith a worm gear 80 mounted on a shaft 82. The shaft 82 is, in turn,supported on a shaft support 84 secured to the adjusting shaft support75. The shaft 82 has an end portion arranged to be engaged by a crank torotate the gear 80 which, in turn, through gear 78 rotates adjustingshaft 74. The rotation of shaft 74 rotates the gears 72 to thus rotatethe end discs 56' and the intermediate discs 56 shaft 68 adjacent thedrive side has connected thereto to change the peripheral distancebetween the front edge grippers 42' and the tail edge grippers 44.

As illustrated in FIG. 9, the tail edge gripper support shaft 60 isarranged to rotate or revolve relative to the main shaft 48, so that thetail edge grippers revolve with the shaft 60 and make one completerevolution per revolution of the shaft 48. The tail edge gripper supportshaft 60 and the tail edge grippers 44 revolve at a variable angularvelocity during the revolution of the transfer cylinder main shaft 48 toextend the tail edge grippers beyond the periphery of the transfercylinder 26, as later described. The rotation of the tail edge grippersupport shaft 60 is controlled by a cam and gear mechanism illustratedin FIGS. 2 and 5.

Referring to FIG. 5, the tail edge gripper support a spur gear 86nonrotatably secured thereto. The spur gear 86 meshes with a spur gearof reduced diameter 88 rotatably mounted on a suitable shaft 90positioned radially inwardly of the tail edge gripper support shaft 60.Nonrotatably secured to gear 88 is a large spur gear 92 which mesheswith a ring gear 94 that extends around the transfer cylinder shaft 48.The ring gear 94 is, in turn, connected to the end of a cylindricalmember 96 that has a second ring gear 98 on the outboard end adjacentthe frame 52. The cylindrical member 96 is supported by bearings onshaft 48.

A spur gear 100 is nonrotatably mounted to a smaller diameter gear 104.Gear 104 is rotatably mounted to shaft 102 journaled in the side frame52. An arm 106 extends around the transfer cylinder shaft 48 and has agear segment 108 meshing with the spur gear 104. The arm 106 has a bore110 through which shaft 112 extends. The shaft 112 is nonrotatablysecured to the arm 106 and is rotatably journaled in bore 114 of theframe 52. A lever arm 116 is nonrotatably secured to the other end ofshaft 112 and has a cam follower 118 secured thereto. The cam follower118, in turn, positioned in the endless cam track 120 on gear 122. Thegear 122 is secured to drive gear 124 which rotates therewith. The gear122 is adjustableradially on gear 124 for different size sheets. Thegear 124 is secured to the transfer cylinder shaft 48 and transmitsrotation to shaft 48 at a constant angular velocity. The cam follower118, by means of cam track 120, pivots the arm 116 to oscillate theshaft 112 and through the arm 106 with gear segment 108 and gear train104, 100, 98, 94, 92, 88 and 86 revolves the tail edge gripper supportshaft 60 at a non-uniform angular velocity to position the tail edgegripper shaft as illustrated in FIG. 9.

The tail edge grippers generally designated by the numeral 44 areillustrated in detail in FIGS. 4, 9, 9a and 9b and include a first arm126 that has an end portion 128 with a semi-circular recess 130 havingsubstantially the same diameter as the tail edge gripper support shaft60 and longitudinally threaded bores 132 therethrough. A clamp endportion 134 has a similar. circular recessed portion 136 andlongitudinal bores 138 therethrough. The clamp end portion 134 ispositioned in overlying relation to the arm end portion 128 and bolts140 extend through the respective apertures to nonrotatably clamp thearm 126 to the tail edge gripper support shaft 60. The arm 126 has anaperture 142 intermediate the end portions and a gripper pad end portion144 on which the tail edge of the sheet is arranged to be positioned.

. i 7 A gripper arm 146 has a gripper finger end portion 148 and adependent intermediate arm 150. The dependent intermediate arm 150 has apivot aperture 151 therethrough arranged in overlying relation with thepivot aperture 142 in arm 126. A pin 149 extends through the aperturesand pivotally connects the arm 126 to the arm 146, so that the gripperfinger end portion 148 is arranged to move toward and away from thegripper pad 144. A pin 152 extends through the lower portion of arm 150and is secured at the other end to the enlarged end portion 128 of arm126. A spring 154 is positioned between the arm 150 and the other endportion 128 of arm 126 and is arranged as viewed in FIG. 4 to pivot thearm 146 in a clockwise direction to move the gripper finger 148 awayfrom the gripper pad 144 to thus open the tail edge grippers 44. Withthis arrangement, the spring 154 continually urges the gripper finger148 away from the gripper pad 144.

A plate member 156 is secured to the arm 146 and is arranged to pivottherewith about the pivot pin 14-9 and has a cam follower 158 thereon. Aspring 159 is positioned on pin 16] and the pin 161 is positioned inrecess 163 in plate 156. The pin 161 is secured to arm 146 and isoperable to adjust the gripper 44 for different sheet thickness. The camfollower 158 is arranged to abut a surface of a cam 160 rotatablypositioned on the tail edge gripper support shaft60. With thisarrangement, the spring 154 urges the gripper finger 148 toward an openposition and further urges the cam follower 158 into abutting relationwith the surface of the cam 160.

.The cam 160, as illustrated in FIGS. 3, 9 and 9b, has

a first arcuate surface 162 which is spaced a sufficient distance fromthe axis of shaft 60 to maintain the tail edge grippers 44 in a closedposition where the gripper finger 148 abuts the gripper pad 144. The cam160 has other cam surfaces 164, which permit the gripper finger 148 tomove from a full open position to a full closed position, and a surface166 that permits the gripper finger 148 to move into a full openposition under the tension exerted by the spring 154. With thisarrangement the tail edge grippers 44 are opened and closed by therelative position of the cam discs 160 associated with each tail edgegripper 44. The discs 160 are rotatably positioned on the tail edgegripper sup port shaft 60 so that the cams 160 can rotate about theshaft 60.

The relative position of the cams 160 on the tail edge gripper supportshaft 60 is controlled by shaft 64 illustrated in FIGS. 3, 4, 9 and 9b.The tail edge gripper actuator shaft 64 has a plurality of levers 168nonrotatably secured thereto. The levers 168 are connected at their endportion by means of rods 170 to the respective cams 160. With thisarrangement rotation of shaft 64 relative to shaft 60 rotates the cam160 to open and close the tail edge grippers 44. The shaft 64 issuitably journaled in the tail edge gripper end discs 56' and has alever member 172 (FIGS. 2 and 3) connected to the end portion adjacentthe frame 50 on the operator's side of the delivery mechanism. Acylindrical member 174 is journaled in an aperture 176 in side frame 50and has an axial passageway to rotatably support the transfer cylindermain shaft 48. The cylindrical memher ,174 has an enlarged circular endportion 178 with an endless cam track 180 therein. A cam follower 182 ispositioned in the cam track 180 and is rotatably connected to lever 172that is, in turn, connected to the end portion of shaft 64. With thisarrangement, the cam follower 182 follows the endless cam track in thefixed member 174 and pivots the arm 172 to thus rotate the shaft 64 witha preselected angular velocity to open the tail edge grippers 44 as thepad 144 of tail edge grippers 44 moves into underlying relation with thetail edge of the sheet and to thereafter close the tail edge grippers 44to engage the sheet. Cam track 180 holds lever 168 stationary, as tailend gripper 44 rotates outward from transfer cylinder 26 as previouslydescribed, and cam follower 158 moves across surface 162 of cam 160.When the sheet has been conveyed to a position in substantiallyoverlying relationship with the pile, cam follower 158 leaves camsurface 162 and tail end gripper 44 opens to release the sheet.

The sheet front edge grippers 42 are secured to a block 184 that is, inturn, secured to the nonrotatable member 74 which is pinned to shaft 48(FIG. 7) by means of bolts. The front edge grippers include an angularmember 186 having a radially extending edge portion 188 that serves as agripper pad. Upstanding shaft supports 190 are secured to the pad 184and have a front edge gripper pad actuator shaft 192 rotatably supportedtherein. The front grippers include a gripper arm 194 rotatablypositioned on the shaft 192, as illustrated in FIGS. 3 and 4. Thegripper arm 194 has a gripper finger 198 that is arranged to abut thegripper pad 188 to engage the front edge of a sheet therebetween. Member200 is clampingly engaged on shaft 192 by bolts 196 and has a pin 202connected thereto. A spring 204 is positioned between the head of thepin 202 and the surface of the gripper arm 194 for adjustment purposes.

Rotation of shaft 192 opens and closes the front edge grippers 42. Theshaft 192 is journaled in the supports 190 and has an end portion 206extending beyond the end disc 56' adjacent the frame 52 on the deliveryside of the delivery mechanism. The shaft end portion 206 isnonrotatably connected to a lever mechanism 208 that has a cam follower210 rotatably secured thereto. A cam member 212 (FIGS. 2 and 6) isnonrotatably secured to a housing 214 which is, in turn nonrotatablysecured to the frame 52. The cam member 212 has an endless cam track 216in which the cam follower 210 connected through lever 208 to shaft 192is positioned.

Rotation of the transfer cylinder main shaft 48 moves the cam follower210 in the cam track 216. The configuration of cam track 216 opens thefront edge grippers 42 as the front edge grippers approach the point oftangency between the sprocket 22 and transfer cylinder 26 and close thefront edge grippers 42 on the front edge of the sheet as the sheet istransferred thereto from the transverse gripper bars 18 on chain 16.Thereafter, the cam track 216 maintains the grippers closed and inengagement with the sheet front edge portion until the transfer cylinderhas revolved to a position where the grippers 36 are tangent to thetransfer cylinder 26. At that location the cam track 216 opens the frontedge grippers 42, so that the front edge of the sheet may be transferredto the grippers 36.

Referring to FIGS. 10 and 12 there is illustrated in top plan and sideelevation a frame member generally designated by the numeral 218 thatincludes a side member 220 adjacent the press operators side frame 50and a side member 222 adjacent the drive side frame 52. The frame 218has transverse members 224 and 226 secured to the respective sidemembers 221) and 222 in spaced relation to each other. An intermediatesupport member 227 is also positioned between side members 220 and 222.A sprocket drive shaft 228 is suitably journaled in the side framemembers 220 and 222 in spaced relation to each other. A plurality ofsprockets 230 are mounted on the sprocket drive shaft 228 for rotationtherewith. Sprocket 232 connected to the end portion of shaft 228 issuitably connected to a drive mechanism and is arranged to rotate at apreselected linear speed.

Extending rearwardly from the transverse member 224 are a plurality ofsprocket supports 234 on which are rotatably mounted idler sprockets236. A plurality of endless chains 34, previously described, are reevedabout drive sprockets 230 and idler sprockets 236. The

endless chains 34 are arranged to be driven at a preselected speed thatis coordinated with the press speed. Positioned adjacent to therespective chains 34 are a plurality of endless gripper tracks or guides28 in which the grippers generally designated by the numeral 36 arepositioned. As later described, the grippers 36 are connected to theadjacent endless chains, so that the endless chains 34 propel thegrippers 36 in the gripper tracks 28.

The frame 218, which supports the endless chains 34 and gripper tracks28, is movable longitudinally relative to the transfer cylinder 26, asillustrated in FIG. 12. The frame 218 has laterally extending shafts 238with rollers 240 rotatably mounted thereon. The rollers 240 have annularV-shaped recessedportions therein. As illustrated in FIG. 11, therollers 240 are supported on members 242 that have an upstanding pointedportion 244 extending into the annular V-shaped recessed portions ofrollers 240. The members 242 are, in turn, sup ported by the sideframes-50 and-52. With this arrangement the frame 218 is movablelongitudinally relative to the side frames 50 and 52 and the transfercylinder 26 mounted thereon; The longitudinal adjustment of theframe'2l8 with the sheet delivery mechanism positioned thereon permitsadjustment for delivery of different sized sheets without relativemovement'of the transfer cylinder 26. I I

As illustrated in FIG. 12, a beam member secured to the frames 50 and 52has a forwardly extending arm 246 on which cam members 248 arepositioned. The

cam members 248 are arranged to open and close the grippers generallydesignated by the numeral 36 so that the grippers 36 engage the leadingedge of the sheet as it is transferred by the transfer cylinder 26. Itshould be noted that the cam member 248 remains fixed relative to thetransfer cylinder 26 and longitudinal movement of frame 218 does notchange the location at which the grippers 36 open to engage the sheet.Secured to the frame transverse member 226 are cam members 250 which arearranged to open the grippers 36 and release the front edge of the sheetas the sheet is deposited on the pile. It should be noted that the camactuator 250 for opening the grippers 36 moves longitudinally with theframe 218.

One of the gripper tracks 28 is illustrated in detail in FIG. 12 andincludes an outer rail 252 and a parallel inner rail 254 with a space256 therebetween. The endless gripper traek 28 has an intermediate lowerportion 258 along which the gripper 36 is conveyed to a front portiongenerally designated by the numeral 260. The intermediate lowerportion258 is at substantially the sameelevation as the lower strand of endlesschain 34 and the gripper track front portion 260 deviates downwardlyalong an arcuate path from the path followed by the chain 34. Thegripper 36 positioned in the gripper track thus follows the downwardlyextending arcuate track front end portion 260 and, as later explained,slows down the forward velocity of the sheet as it is released.

The gripper 36 is illustrated in detail in FIGS. 13 l7 and includes afirst plate member 262 with a pair of rollers 264 and 266 positioned inthe track opening 256. The rollers have shafts 268 and 270 that aresecured to a second plate 272 on the opposite side of the gripper track28. With this arrangement the plate 262 follows the path of the grippertrack 256. The plate 262 has a depending arm portion 272 with a gripperfinger 274 pivotally secured thereto about pivot pin 276. A lever 278 isconnected through pivot pin 276 to gripper finger 274 and has a camfollower 280 secured to the end portion thereof. A gripper pad 282 issecured to the plate depending arm portion 272 and the gripper finger274 is arranged to abut the pad 282 and hold the front edge of the sheettherebetween. A spring 284 is connected to the gripper 274 and plate 262to urge the gripper finger 274 into abutting relation with the gripperpad 282. With this arrangement the lever 278 through cam follower 280 isarranged to move the gripper finger 274 away from the gripper pad 282 inresponse to cam surfaces 248 and 250.

The grippers 36 are connected to the respective adjacent chains 34 by anadjustable "push rod 286 connected through ball type joints 288 torespective shafts 290 on chain 34 and shaft 270 on grippers 36. Withthis arrangement the grippers 36 are propelled by the respectiveadjacent chains 34 and open adjacent the transfer cylinder 26 to engagethe front edge of the sheet and propel the sheet toward the front edgeof the frame 218 where the cam 250 opens the grippers 36 and releasesthe sheet. v

The grippers 36 by following the arcuate portion 260 of the cam trackare arranged to slowdown the forward movement of the sheet as the chains34 continue to move at the same velocity. As the gripper 36 is pushedinto the arcuate portion 260 of track 256 one end of the rod 286 followsthe chain path while the other end of the rod follows the arcuateportion 260 of the cam track. The counterclockwise motion of the pushrod, as illustrated in FIGS. 16 and 17, slows down the entire gripperassembly relative to chain speed because the gripper assembly traversesa greater linear distance than the propelling chain reeved aboutsprockets 230 and 236.

In addition, the two rollers 264 and 266 in the gripper assembly 36follow the arcuate downwardly extending portion of the gripper track 260and pivot the entire gripper 36 in a counterclockwise direction aboutthe end of the push rod 286 that follows the cam or arcuate portion 260of the cam track. The slowdown of the gripper 36 is accomplished by acombination of the push rod 286 pivoting counterclockwise and thegripper assembly 36 also pivoting counterclockwise. This slowdown of thegrippers is arranged to match the slowdown of the tail grippers 44; thusmaintaining the sheet straight asit is brought over the pile. Theconveyor grippers 36 release the sheet first and then the tail endgrippers 44 release the tail of the sheet thereafter. This ill permitsthe sheet to be deposited on the pile without flutter and the like.

According to the provisions of the patent statutes, I have explained theprinciple, preferred construction and mode of operation of my inventionand have illustrated and described what I now consider to represent itsbest embodiments. However, it should be understood that, within thescope of the appended claims, the invention may be practiced otherwisethan as specifically illustrated and described.

I claim:

1. A sheet delivery mechanism for delivering sheets from a printing unitto a pile comprising,

a first endlessconveyor having sheet engaging means thereon,

an intermediate transfer cylinder rotatably mounted between said firstendless conveyor and a pile of sheets, said intermediate transfercylinder having sheet engaging means thereon,

said sheet engaging means includes sheet front edge engaging devices andsheet tail edge engaging devices,

a second endless conveyor having sheet engaging means thereon positionedadjacent to said intermediate transfer cylinder and in overlyingrelation with said pile,-

said first endless conveyor sheet engaging means arranged to engage thefront edge of a sheet and convey said sheet from a printing unit to saidintermediate transfer cylinder,

said intermediate transfer cylinder arranged to transfer the front edgeof the sheet from said first endless conveyor to said second endlessconveyor sheet engaging means,

said second endless conveyor sheet engaging means arranged to .engagethe front edge of said sheet and convey the sheet into overlyingrelation with said pile,

said intermediate transfer cylinder arranged to engage the sheet frontedge transferred from said first endless conveyor sheet engaging meanswith said sheet front edge engaging devices and transfer said sheetfront edge to said second endless conveyor sheet engaging means whilesaid sheet tail edge remains engaged by said intermediate transfercylinder sheet tail edge engaging devices, and

means to release said sheet front edge from said second endless conveyorsheet engaging means while said sheet tail edge remains engaged by saidintermediate transfer cylinder sheet tail edge engaging means.

2. A sheet delivery mechanism as set forth in claim which includes,

means to reduce the forward speed of said second endless conveyor sheetengaging means while said sheet tail edge remains engaged by saidintermediate transfer cylinder sheet tail edge engaging devices.

3. A sheet delivery mechanism as set forth in claim 1 which includes,

means to move said second endless conveyor toward and away from saidintermediate transfer cylinder so that sheets of different length may bedelivered from said printing unit to a pile.

4. A sheet delivery mechanism as set forth in claim 3 which includes,

Lil

first actuating means fixedly mounted relative to said intermediatetransfer cylinder, said first actuating means operable to actuate saidsecond conveyor sheet engaging means for engaging the front edge of asheet transferred from said intermediate transfer cylinder,

second actuating means fixedly mounted relative to said second endlessconveyor, said second actuating means operable to actuate said secondconveyor sheet engaging means to release the front edge of a sheet whensaid sheet is in overlying relation with a pile.

5. A sheet delivery mechanism as set forth in claim 1 which includes,

means to reduce the forward speed of said second endless conveyor sheetengaging means as said second endless conveyor sheet engaging meansapproaches the front edge of the pile.

6. A method for delivering a sheet from a printing unit to a pilecomprising,

engaging the front edge of a sheet by a first endless conveyor whilesaid sheet is in a printing unit,

conveying the sheet by said first endless conveyor to an intermediatetransfer cylinder,

transferring the front edge of said sheet to sheet engaging devices onsaid intermediate transfer cylinder,

engaging the front edge of the sheet by said sheet engaging devices onsaid intermediate transfer cylinder,

engaging the tail edge of the sheet by other sheet engaging devices onsaid transfer cylinder,

rotating said transfer cylinder at a preselected speed,

transferring the front edge of the sheet from said intermediate transfercylinder to sheet engaging means on a second endless conveyor,

engaging the front edge of said sheet by said sheet en gaging means onsaid second endless conveyor,

conveying said sheet on said second endless conveyor to a pilepositioned therebelow,

disengaging said sheet front edge from said second endless conveyorsheet engaging means and depositing said sheet on a pile, and

maintaining the tail edge of the sheet engaged by said sheet engagingdevices on said sheet transfer cylinder until said sheet front edgeportion is disengaged from said second endless conveyor sheet engagingmeans.

7. A method for delivering a sheet from a printing unit to a pile as setforth in claim 6 which includes,

reducing the forward speed of said sheet as the front edge of the sheetapproaches the front edge of the pile.

1. A sheet delivery mechanism for delivering sheets from a printing unitto a pile comprising, a first endless conveyor having sheet engagingmeans thereon, an intermediate transfer cylinder rotatably mountedbetween said first endless conveyor and a pile of sheets, saidintermediate transfer cylinder having sheet engaging means thereon, saidsheet engaging means includes sheet front edge engaging devices andsheet tail edge engaging devices, a second endless conveyor having sheetengaging means thereon positioned adjacent to said intermediate transfercylinder and in overlying relation with said pile, said first endlessconveyor sheet engaging means arranged to engage the front edge of asheet and convey said sheet from a printing unit to said intermediatetransfer cylinder, said intermediate transfer cylinder arranged totransfer the front edge of the sheet from said first endless conveyor tosaid second endless conveyor sheet engaging means, said second endlessconveyor sheet engaging means arranged to engage the front edge of saidsheet and convey the sheet into overlying relation with said pile, saidintermediate transfer cylinder arranged to engage the sheet front edgetransferred from said first endless conveyor sheet engaging means withsaid sheet front edge engaging devices and transfer said sheet frontedge to said second endless conveyor sheet engaging means while saidsheet tail edge remains engaged by said intermediate transfer cylindersheet tail edge engaging devices, and means to release said sheet frontedge from said second endless conveyor sheet engaging means while saidsheet tail edge remains engaged by said intermediate transfer cylindersheet tail edge engaging means.
 2. A sheet delivery mechanism as setforth in claim 1 which includes, means to reduce the forward speed ofsaid second endless conveyor sheet engaging means while said sheet tailedge remains engaged by said intermediate transfer cylinder sheet tailedge engaging devices.
 3. A sheet delivery mechanism as set forth inclaim 1 which includes, means to move said second endless conveyortoward and away from said intermediate transfer cylinder so that sheetsof different length may be delivered from said printing unit to a pile.4. A sheet delivery mechanism as set forth in claim 3 which includes,first actuating means fixedly mounted relative to said intermediatetransfer cylinder, said first actuating means operable to actuate saidsecond conveyor sheet engaging means for engaging the front edge of asheet transferred from said intermediate transfer cylinder, secondactuating means fixedly mounted relative to said second endlessconveyor, said second actuating means operable to actuate said secondconveyor sheet engaging means to release the front edge of a sheet whensaid sheet is in overlying relation with a pile.
 5. A sheet deliverymechanism as set forth in claim 1 which includes, means to reduce theforward speed of said second endless conveyor sheet engaging means assaid second endless conveyor sHeet engaging means approaches the frontedge of the pile.
 6. A method for delivering a sheet from a printingunit to a pile comprising, engaging the front edge of a sheet by a firstendless conveyor while said sheet is in a printing unit, conveying thesheet by said first endless conveyor to an intermediate transfercylinder, transferring the front edge of said sheet to sheet engagingdevices on said intermediate transfer cylinder, engaging the front edgeof the sheet by said sheet engaging devices on said intermediatetransfer cylinder, engaging the tail edge of the sheet by other sheetengaging devices on said transfer cylinder, rotating said transfercylinder at a preselected speed, transferring the front edge of thesheet from said intermediate transfer cylinder to sheet engaging meanson a second endless conveyor, engaging the front edge of said sheet bysaid sheet engaging means on said second endless conveyor, conveyingsaid sheet on said second endless conveyor to a pile positionedtherebelow, disengaging said sheet front edge from said second endlessconveyor sheet engaging means and depositing said sheet on a pile, andmaintaining the tail edge of the sheet engaged by said sheet engagingdevices on said sheet transfer cylinder until said sheet front edgeportion is disengaged from said second endless conveyor sheet engagingmeans.
 7. A method for delivering a sheet from a printing unit to a pileas set forth in claim 6 which includes, reducing the forward speed ofsaid sheet as the front edge of the sheet approaches the front edge ofthe pile.